The present invention relates to arrangement of vehicle components within an engine compartment, and in particular to an integrated air box, washer reservoir and acoustic resonator unit.
Motor vehicle engine compartments must accommodate, in addition to the vehicle's engine, a large variety of associated engine support system components, such as the engine air intake and filtration system housings, engine cooling radiator, hoses and fans, transmission cooling system components, electrical storage and distribution system components, heating and air conditioning system components, etc. Additionally, other non-drivetrain-related vehicle components, such as windshield wiper drive mechanisms and windshield and headlight washer system components, are often located in the engine compartment if necessary or convenient.
Traditionally, engine and drivetrain support system components have been individually designed and manufactured. Vehicle designers therefore have concentrated on finding a suitable location in the engine compartment for each individual component and adapting the component to the available space if necessary. This approach to vehicle design necessarily involves compromises, particularly in smaller vehicles where under-hood space is at a premium. For example, it may be desirable to locate an engine air intake pipe and filter housing directly adjacent to an engine intake manifold in order to minimize intake air flow resistance and thereby increase engine power output by increasing the amount of air drawn into the engine during the intake stroke. However, the air intake system typically ends up having its primary components (such as its filter housing) located at some distance from the intake manifold due to underhood space constraints, such as the need to fit the engine air intake pipe and filter housing under a desired hood shape, the need to accommodate the presence of other system components such as hoses, accessory belts, dipstick tubes, etc. near the air intake, and the need to share the scarce available under-hood volume with various components such as fluid reservoirs and the storage battery. The result is less-than-optimum intake air flow through a long, contorted air intake path extending, for example, between an air inlet near an inner fender and the engine intake manifold.
A further concern with current engine compartment arrangements is the loss of a significant amount of under-hood space as a result of the need to provide excess clearance between adjacent individual support system components. Such clearance must be provided to ensure the components do not damage one another due to, for example, relative motion during the operation of the vehicle or excessive component-to-component heat transfer, and to provide sufficient clearance to facilitate servicing of the components without undue interference from adjacent components.
Also becoming a greater concern is the need to meet increasingly strict radiated noise standards, as well as customer expectations for minimal drivetrain-generated noise in the passenger compartment. Previously, engine components have been formed in ways which have not significantly reduced radiated noise. For example, FIG. 6 shows a cross-sectional view of a prior art component sidewall, with a plastic outer wall 601 to which is bonded a corresponding pad 602, such as a fiber mat or foam layer. Similarly, FIGS. 7 and 8 show oblique inside views of a prior art plastic outer wall shell 701 and a molded foam liner 801 which is bonded to the plastic shell 701. These component sidewall structures have a number of practical disadvantages, however. For example, in many applications the inner foam liner must be chemically treated to provide fire resistance in the face of high underhood temperatures, the fire-retardant chemicals are often toxic, and due to the high temperatures, simpler (i.e., lower-cost) foam materials cannot be used. Further, because the foam or fiber mat materials cannot be recycled with the plastic outer shell, it must be separated from the shell, increasing recycling process difficulty and cost.